A complete power failure mid-ocean is thankfully rare, and it is usually the charging system that fails rather than batteries, writes Chris Tibbs. That said, when we bought our boat the batteries were so poor that once disconnected from shore power they only lasted a couple of hours before being completely discharged.

Nowadays it is unusual to find yachts with only one battery bank and without a dedicated engine start battery. Many of us have experienced selector switchers that can be left in the wrong position, so I prefer a set up so that it is impossible to link batteries like this. One boat I looked after had a paralleling switch to temporarily link all the batteries should the engine start battery not be up to the job. This had to be held in place so it could not be left on; we use a simpler solution and carry jump leads.

Long distance cruising yachts will usually have more than one means of charging the batteries and the majority of cruisers have solar, wind vanes, or hydrogenerators to back up the engine. Whilst these may go through one single regulator, each system will often have its own regulator adding some redundancy and backup.

Get your priorities right

If you have lost power production you need to reduce consumption and prioritise; top of my list is navigation lights – a masthead LED tricolour draws around 0.3A which even on a tropical passage with long nights is less than 3.5ampare hours. It also has the added advantage of lighting up the windex so we can reduce the time we use instruments.

The compass light is also important and this may draw as much or more than the tricolour, but steering at night is difficult without this reference point, particularly without nav instruments.

The Seraphina crew (below) crossed the Atlantic the old fashioned way – paper charts and log books

On an ocean passage like the Atlantic you do not need to know our position at all times, once or twice a day is adequate. This does mean that chart plotters can be turned off, and the GPS used only a couple of times a day to log position. A handheld from the grab bag can be used for this, as can the handheld VHF, as long as you have enough spare batteries.

High on the list of priorities must be starting the engine in case of an emergency; if all the batteries are connected together, as in Seraphina’scase (see right), it may be possible to mechanically split the batteries and use the solar panel (or petrol generator) to charge the engine start battery and keep it isolated for emergency use. I would also look at which batteries were in the best condition and reduce the number of batteries in the bank to try and get a couple of batteries to a reasonable level rather than all of them to a low level. By careful monitoring it should then be possible to prevent a total discharge.

On smaller and particularly older engines there may be decompressors to facilitate hand starting. I’ve never had much success hand-starting engines but have found it possible with a weak battery to decompress the cylinders, which then requires less power to turn the engine over before dropping the decompressor, as if hand starting.

Whilst AIS is a brilliant invention and I would not like to be without it, it is no substitute for keeping a good watch and in areas of good visibility, particularly in daylight, I would turn it off, or set to ‘receive only’ to save power. On a dark windy night it can be turned on again but I would rather have two crew on watch and hand steering for safety. Hand steering keeps us alert and I think much better watch keepers. The AIS alarm and MOB is essential, particularly if one person is watch keeping, so a balance needs to be found between conserving power and safety.

Small changes in the daily routine can also help save on power, having your evening meal before darkness will get food preparation and clearing away done without needing lights. Solar powered cockpit lights have become common and these can be used below when making drinks at night or visiting the heads.

Having to rely on a pressurised water system is not great and an additional foot pump is very useful. We do not have a foot pump on our boat so we carry a small syphon pump in case of electric pump failure as it is possible to get to the tops of the tanks and pump it out manually.

You can live quite comfortably on limited power – on my first ocean passage from the Virgin Islands to Bermuda without a fridge we had a very strict rule and only opened the ice box once a day to get food out. Seven days later arriving in Bermuda we still had ice. This may work for a freezer but the fridge would quickly warm and foods spoil. Just like you would not rely on one tank of water neither should you rely on one source of food. It may seem old fashioned but a good supply of tinned food is worth carrying; many have their own liquid which also reduces the dependence on watermakers.

With full-on trade winds, hand steering all the way will tire the crew so when short-handed the autopilot becomes more important to avoid excess fatigue. If you are two handed and restricting your autopilot use then reducing sail or even heaving to for a rest are options, however a good watch still needs to be kept for other vessels.

The Dufour Sortilege Seraphina

A dark transat

In November 2017 I joined the ARC+ on the Dufour Sortilege Seraphina, a 12.5m centre cockpit ketch, writes Valentina Vela.

On 15th November we left Cape Verde on our way to Saint Lucia and the first couple of days of our transat were pretty smooth. But on the early morning of our third day at sea, the battery level was unexpectedly low.

The yacht’s core power system was based on seven batteries, one starting and six house batteries, charged by an alternator connected to the diesel engine. As back up, there was a small solar panel and a portable petrol generator.

As soon as we got the first alarm flagging that we had an issue we turned the diesel engine on to recharge our batteries through the alternator. We were still wondering what caused such a high power consumption during the night (maybe radar or autopilot) when we joined the 0900 fleet daily chat on the SSB radio. But, after few minutes of transmission, our SSB switched off. All our batteries were completely flat, although our diesel engine was still running in an attempt to recharge them.
We left the engine running for another few hours but made no progress, so we decided to use the portable petrol generator. Slowly we got some power back into the batteries, and realised that the alternator was not working properly.

The crew hand steered and used a wind vane after power failure left them without an autopilot

For two days we kept testing and attempting different repairs, using the generator to produce the power required to re-start the diesel engine again and again. During our tests we discovered that the power system had not been implemented as designed: the starting battery was not isolated from the other six house batteries, and all of them were part of the same circuit. So the charging problem was also impacting our engine starting system.

With only two small 4-litre tanks of petrol onboard and a minimum of two hours required to recharge the batteries, using the generator was not a viable option to produce power for the entire crossing. It could only be used from time to time, to avoid damaging the batteries by letting them experience multiple deep discharge cycles in a row (due to the solar panel), or to start the diesel engine in a distress situation.

After a long discussion, we decided to keep going with our transatlantic, despite not having any power, and began putting in place all the workarounds that became our new routine.

Not being able to immediately turn the diesel engine on to complete a recovery manoeuvre was our main concern. Obviously a man overboard situation was the worst scenario an, unfortunately, even the AIS MOB devices installed in all our lifejackets wouldn’t be any help without power to run our VHF system. To mitigate such a huge risk, I started wearing my lifejacket and Personal Locator Beacon all the time and routinely clipping myself on at night and during daylight when out of the cockpit (to work at the mast or the bow).

Being unable to use any radio (except a handheld VHF) our only way to send a distress message if needed would be through our sat phone. To conserve its batteries, we decided to turn it on only once per day to download emails with weather forecasts and other notifications from the ARC rally control team.

With no navigation lights, radar or AIS, collision avoidance was another significant safety issue. The risk of heavy weather was another concern because we wouldn’t be able to quickly reef the main in the case of an approaching squall because we had an electric winch on the halyard. For the last two points we had no real workaround, only a commitment as a team to be 100% focused all the time when on watch and to put our trust in each other.

Seraphina’s route was mapped on the YB tracker – the team finished 4th in their division

More minor challenges including having no sailing instruments to track wind direction and speed, but we quickly improved our ability to feel the wind. We had no electronic plotter, but did have a small handheld GPS powered by standard AAA batteries, combined with a good compass and detailed charts which saw us safely navigate across the Atlantic. We also had no autopilot, but an old-fashioned wind-vane helped steer all the way to the Caribbean.

Life in the darkWith no fridge, we had to hurry to consume all the fresh perishable food and move on to the preserved stores. We had no lights, but our head torches covered basic needs, allowing us to prepare a warm coffee at night as much as double check the sails or rig during night watches.

For the first ten days, the solar panel was able to daily recharge our batteries enough to power the solenoid valves installed on the gas stove and the electric water pump to transfer water from the tank to some empty bottles every day. By day 18 of our crossing, probably because of the progressive decay of the batteries, the solar panel wasn’t anymore able to squeeze any power into our batteries. So during the last couple of days, we used a small camping gas stove to cook and manually pumped water out of the tank to fill the bottles.

Arriving safely in St Lucia

The YB Tracker installed onboard had his own battery, so families and friends were able to keep monitoring our daily progress on the YB Racer App. Moreover, the YB Tracker allowed us to send and receive short messages to stay in touch with our families on a daily basis. And, thanks to a small USB solar charger, we were also able to regularly recharge our smartphones, tablets, and an mp3 player for music.

With all these small workarounds in place, on 5th December after 20 days at sea, we safely landed in St Lucia proud of having completed a transatlantic crossing the ‘old-fashioned’ way.